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We investigate the turbulence statistics in a multiphase plume made of heavy particles (particle Reynolds number at terminal velocity is 450). Using refractive-index-matched stereoscopic particle image velocimetry, we measure the locations of particles whose buoyancy drives the formation of a multiphase plume, together with the local velocity of the induced flow in the ambient salt–water. Measurements of the mean axial flow in the plume centreplane follow Gaussian profiles and that of the mean radial flow is consistent with integral plume theory. The turbulence characteristics resemble those measured in a bubble plume, including strong anisotropy in the normal Reynolds stresses. However, we observe structural differences between the two multiphase plumes. First, the skewness of the probability density function of the axial velocity fluctuations is not that which would be predicted by simply reversing the direction of a bubble plume. Second, in contrast to a bubble plume, the particle plume has a non-negligible fluid-shear production term in the turbulent kinetic energy (TKE) budget. Third, the radial decay of all measured terms in the TKE budget is slower than those in a bubble plume. Despite these dissimilarities, a bigger picture emerges that applies to both flows. The TKE production by particles (or bubbles) roughly balances the viscous dissipation, except near the plume centreline. The one-dimensional power spectra of the velocity fluctuations show a
power law that puts both the particle and bubble plume in a category different from single-phase shear-flow turbulence.
Often referred to as psychotic experiences, unusual perceptual experiences, thoughts and beliefs (UPTBs) are not uncommon in youth populations. Phenomenological studies of these experiences are lacking. This study aimed to (1) describe the phenomenological characteristics of UPTBs in a sample of young adolescents and (2) explore how young people made sense of those experiences.
Participants were 53 young people aged 11–13 years from a population-based study of mental health. All met criteria for UPTBs following clinical interviews as part of the study. Documentary data on UPTBs in the form of transcribed notes, recorded during clinical interviews, were analysed using content analysis. Data on UPTBs were coded, organised into categorical themes and quantified using descriptive statistics. Qualitative themes on how participants made sense of their experiences were identified.
Participants reported UPTBs across four domains: auditory verbal, auditory non-verbal, non-auditory perceptual experiences and unusual thoughts and beliefs. UPTBs were phenomenologically rich and diverse. Young people sought to make sense of their experiences in multiple ways: normalising them, externalising them by attributing them to paranormal entities and distancing them from psychiatric explanations. Uncertainty about the source of UPTBs was identified as a superordinate theme.
Findings from this study offer new insights into the phenomenological qualities and characteristics of UPTBs in young adolescents. They also reveal that early adolescents may not make sense of their experiences within a psychiatric framework. These findings highlight the need to develop a more phenomenologically sensitive and nuanced approach to studying UPTBs in young people.
Introduction: In 2018, Canadian postgraduate specialist Emergency Medicine (EM) programs began implementing a competency-based medical education (CBME) assessment system. To support improvement of this assessment program, we sought to evaluate its short-term educational outcomes nationally and within individual programs. Methods: Program-level data from the 2018 resident cohort were amalgamated and analyzed. The number of Entrustable Professional Activity (EPA) assessments (overall and for each EPA) and the timing of resident promotion through program stages was compared between programs and to the guidelines provided by the national EM specialty committee. Total EPA observations from each program were correlated with the number of EM and pediatric EM rotations. Results: Data from 15 of 17 (88.2%) EM programs containing 9,842 EPA observations from 68 of the 77 (88.3%) Canadian EM specialist residents in the 2018 cohort were analyzed. The average number of EPAs observed per resident in each program varied from 92.5 to 229.6 and correlated strongly with the number of blocks spent on EM and pediatric EM (r = 0.83, p < 0.001). Relative to the guidelines outlined by the specialty committee, residents were promoted later than expected and with fewer EPA observations than suggested. Conclusion: We present a new approach to the amalgamation of national and program-level assessment data. There was demonstrable variation in both EPA-based assessment numbers and promotion timelines between programs and with national guidelines. This evaluation data will inform the revision of local programs and national guidelines and serve as a starting point for further reaching outcome evaluation. This process could be replicated by other national assessment programs.
Introduction: Hyperkalemia is a common electrolyte disturbance associated with morbidity and mortality. Commonly used therapies for hyperkalemia include IV calcium, sodium bicarbonate, insulin, beta-adrenergic agents, ion-exchange resins, diuretics and hemodialysis. This study aims to evaluate which treatments are more commonly used to treat hyperkalemia and to examine factors which influence those clinical decisions. Methods: This is a retrospective chart review of all cases of hyperkalemia encountered in 2017 at a Canadian adult ED. Potassium values were classified as mild (5.5 - 6.5 mEq/L), moderate (>6.5 - 7.5 mEq/L) and severe (>7.5 mEq/L). Treatment choices were then recorded and matched to hemodynamic stability, degree of hyperkalemia and ECG findings. More statistical methods to test correlation between treatment and specific variables will be performed over the next 2 months, including logistic regression to highlight potential determinants of treatment and Chi-square tests to verify randomness and to construct 95% confidence intervals. Results: 1867 ED visits were identified, of which 479 met the inclusion criteria. 89.1% of hyperkalemia cases were mild, 8.2% were moderate, and 2.7% were severe. IV insulin was used in 22.1% of cases, followed by Kayexalate in 20.5%, sodium bicarbonate in 12.3%, IV calcium in 9.4%, frusemide in 7.3%, salbutamol in 2.7%, and dialysis in 1.9%. Moderate and severe hyperkalemia were associated with higher use of insulin (79.5% and 64.3% respectively), IV calcium (41% and 64.3% respectively), sodium bicarbonate (56.4% and 85.7% respectively). Bradycardia was associated with higher insulin and IV calcium use (46.7% and 33.3% respectively). Hypotension was associated with a similar increase in use of insulin and IV calcium (34.2% and 23.7% respectively). There were only 15 cases of cardiac arrest in which sodium bicarbonate and IV calcium were more frequently used (80% and 60% respectively). Conclusion: This study demonstrates variability in the ED management of hyperkalemia. We found that Insulin and Kayexalate were the 2 most common interventions, with degree of hyperkalemia, bradycardia and hypotension influencing rates of treatment. Overuse of kayexalate for emergent treatment of hyperkalemia is evident despite weak supporting evidence. Paradoxically, beta adrenergic agents were underutilized despite their rapid effect and safer profile. The development of a widely accepted guideline may help narrow the differences in practice and potentially improve outcomes.
Introduction: The Brain Injury Guidelines (BIG) stratifies complicated mild traumatic brain injury (mTBI) patients into 3 groups to guide hospitalization, neurosurgical consultation and repeat head-CT. BIG-1 patients could be managed safely without neurosurgical consultation or transfer. Systematic transfer to neurotrauma centers provide few benefits to this subgroup leading to overtriage. Similarly, unnecessary clinical and radiological follow-ups utilize significant health-care resources. Objective: to validate the safety and efficacy of the BIG for complicated mTBIs. Methods: We performed a multicenter historical cohort study in 3 level-1 trauma centers in Quebec. Patients ≥16 years old assessed in the Emergency Department (ED) with complicated mTBI between 2014 and 2017 were included. Patients with penetrating trauma, cerebral aneurysm or tumor were excluded. Clinical, demographic and radiological data, BIG variables, TBI-related death and neurosurgical intervention were collected using a standardized form. A second reviewer assessed all ambiguous files. Descriptive statistics, over- and under-triage were calculated. Results: A total of 342 patients’ records were assessed. Mean age was 63 ± 20,7 and 236 (69 %) were male. Thirty-five patients were classified under BIG-1 (10.2%), 110 under BIG-2 (32.2%) and 197 under BIG-3 (57.6%). Twenty-six patients (7%) required neurosurgical intervention, all were BIG-3. 90% of TBI-related deaths occurred in BIG-3 and none were classified BIG-1. Among the 192 transfers (51%), 14 were classified under BIG-1 (7.3%) and should not have been transferred according to the guidelines and 50 under BIG-2 (26%). In addition, 40% of BIG-1 received a repeat head computed tomography, although not indicated. Similarly, 7 % of all patients had a neurosurgical consult even if not required. Projected implementation of BIG would lead to 47% of overtriage and 0.3% of undertriage. Conclusion: Our results suggest that the Brain Injury Guidelines could safely identify patients with negative outcomes and could lead to a safe and effective management of complicated mTBI. Applying these guidelines to our cohort could have resulted in significantly fewer repeat head CTs, neurosurgical consults and transfers to level 1 neurotrauma centers.
Introduction: An important challenge physicians face when treating acute heart failure (AHF) patients in the emergency department (ED) is deciding whether to admit or discharge, with or without early follow-up. The overall goal of our project was to improve care for AHF patients seen in the ED while avoiding unnecessary hospital admissions. The specific goal was to introduce hospital rapid referral clinics to ensure AHF patients were seen within 7 days of ED discharge. Methods: This prospective before-after study was conducted at two campuses of a large tertiary care hospital, including the EDs and specialty outpatient clinics. We enrolled AHF patients ≥50 years who presented to the ED with shortness of breath (<7 days). The 12-month before (control) period was separated from the 12-month after (intervention) period by a 3-month implementation period. Implementation included creation of rapid access AHF clinics staffed by cardiology and internal medicine, and development of referral procedures. There was extensive in-servicing of all ED staff. The primary outcome measure was hospital admission at the index visit or within 30 days. Secondary outcomes included mortality and actual access to rapid follow-up. We used segmented autoregression analysis of the monthly proportions to determine whether there was a change in admissions coinciding with the introduction of the intervention and estimated a sample size of 700 patients. Results: The patients in the before period (N = 355) and the after period (N = 374) were similar for age (77.8 vs. 78.1 years), arrival by ambulance (48.7% vs 51.1%), comorbidities, current medications, and need for non-invasive ventilation (10.4% vs. 6.7%). Comparing the before to the after periods, we observed a decrease in hospital admissions on index visit (from 57.7% to 42.0%; P <0.01), as well as all admissions within 30 days (from 65.1% to 53.5% (P < 0.01). The autoregression analysis, however, demonstrated a pre-existing trend to fewer admissions and could not attribute this to the intervention (P = 0.91). Attendance at a specialty clinic, amongst those discharged increased from 17.8% to 42.1% (P < 0.01) and the median days to clinic decreased from 13 to 6 days (P < 0.01). 30-day mortality did not change (4.5% vs. 4.0%; P = 0.76). Conclusion: Implementation of rapid-access dedicated AHF clinics led to considerably increased access to specialist care, much reduced follow-up times, and possible reduction in hospital admissions. Widespread use of this approach can improve AHF care in Canada.
The endothelial glycocalyx layer (EGL) is a brush-like layer that lines the internal surfaces of blood vessels. It is thought to serve a number of physiological functions, including as a mechanotransducer of fluid loadings to the vessel wall. However, the fragility of the EGL makes it difficult to examine experimentally, and so there is much value in theoretical models that can help to explain the dynamical behaviour of the EGL. Most previous models have employed mixture theory to mechanically describe the layer, which treats the EGL as a isotropic linearly poroelastic layer. However, there is increasing experimental evidence to suggest that the EGL has a well-defined organisational structure that might not necessarily be well captured by such mixture theory descriptions. We therefore employ homogenisation theory to incorporate into the models some of the possible EGL microstructure suggested by the current biological literature. We explore how mechanotransduction varies under the different possible EGL microstructures, which potentially has important consequences to our understanding of how structural changes to the EGL might affect a vessel’s ability to respond to hemodynamical cues. We also find that, whereas mechanotransduction through the solid components of the EGL is dominated by the fluid tractions applied at the lumen–EGL interface, the component carried through its fluid phase is most sensitive to pressure gradients within the bulk EGL. This is relevant, since it is known that the underlying endothelial cells respond differently to these two different forms of mechanical loading.
Although genetic and environmental factors operating before or around the time of birth have been demonstrated to be relevant to the aetiology of the major psychoses, a seasonal variation in the rates of admission of such patients has long been recognised. Few studies have compared first and readmissions. This study examined for seasonal variation of admission in the major psychoses, and compared diagnostic categories by admission status. Patients admitted to Irish psychiatric inpatient facilities between 1989 and 1994 with an ICD-9/10 diagnosis of schizophrenia or affective disorder were identified from the National Psychiatric Inpatient Reporting System (NPIRS). The data were analysed using a hierarchical log linear model, the chi-square test, a Kolmogorov-Smirnov (KS) type statistic, and the method of Walter and Elwood. The hierarchical log linear model demonstrated significant interactions between the month of admission and admission order (change in scaled deviance 28.77, df = 11, P < 0.003). Both first admissions with mania, and readmissions with bipolar affective disorder exhibited significant seasonality. In contrast, only first admissions with schizophrenia showed significant seasonal effects. Although first admissions with mania and readmissions with bipolar disorder both show seasonality, seasonal influences appear to be more relevant to onset of schizophrenia than subsequent relapse.
Having a diagnosis of schizophrenia is a risk factor for involuntary admission to psychiatric inpatient care, but we have a limited understanding of why some patients and not others require involuntary admission. We aimed to identify the predictors of involuntary admission in first episode schizophrenia. We used validated instruments to assess clinical and socio-demographic variables in all patients (n = 78) with first episode schizophrenia from a defined geographical area admitted to a Dublin psychiatric hospital over a 4-year period. Involuntary patients (n = 17) could not be distinguished from voluntary patients (n = 61) on the basis of age, gender, living status, marital status, drug abuse or duration of untreated psychosis. Neither positive nor negative symptoms were useful predictors of admission status. Lack of insight was a strong predictor of involuntary status.
The aim of this study was to identify the features of first episode schizophrenia that predict adherence antipsychotic medication at six-month follow-up. We used validated instruments to assess clinical and socio-demographic variables in all patients with first episode schizophrenia from a defined geographical area admitted to a Dublin psychiatric hospital over a four-year period (N = 100). At six-month follow-up (N = 60) we assessed adherence to medication using the Compliance Interview. One third of patients with schizophrenia were non-adherent with medication within six months of their first episode of illness. High levels of positive symptoms at baseline, lack of insight at baseline, alcohol misuse at baseline and previous drug misuse predict non-adherence. These results indicate that an identifiable subgroup of patients with first episode schizophrenia is at high risk of early non-adherence to medication. While high positive symptom scores pre-date and predict non-adherence in most patients, reduced insight is the best predictor of non-adherence in patients who do not misuse alcohol or other drugs.
The increased uptake of evidence from systematic reviews is advocated because of their potential to improve the quality of patient care. However, research suggests that evidence from systematic reviews has not been widely adopted. Little is known about the factors that impact on systematic review uptake.
To identify how uptake of evidence from systematic reviews can be enhanced.
We searched 19 databases covering the full range of publication years, utilizing three search engines. Study selection Reports of strategies improving systematic review uptake were selected and evaluated according to the Effective Practice and Organisation of Care criteria.
Two reviewers independently assessed quality and extracted data from each outcome study.
Ten publications addressing interventions met inclusion criteria. Following a systematic review of these studies, a further broader synthesis of findings was carried out to determine the extent to which the identified interventions overcame already identified barriers and built on perceived facilitators.
Strategies such as targeted messaging, educational visits, and summaries, addressed a range of barriers and facilitators and are recommended to enhance uptake of systematic reviews and meta-analyses. Promising approaches such as inactive workshops, e-learning programmes and computer-based approaches need to be developed further. New strategies need to be designed that address a number of identified but neglected barriers and facilitators. This review has added value. It addressed not just effectiveness but also appropriateness of knowledge uptake strategies. It allowed the development of an intervention to enhance evidence uptake in psychiatry.
The comparative effectiveness of antidepressant medication and cognitive-behaviour therapy for the acute treatment of depression is contentious.
To compare the acute outcomes of antidepressant medication, cognitive-behaviour therapy (CBT), and the combination of the two, in adult, depressed patients.
Sixteen electronic databases together with reference lists were searched for randomised and other clinical trials that compared CBT, antidepressants, or their combination.
In the comparison between CBT and antidepressants, 8 studies met inclusion criteria. Five studies met the inclusion criteria for the second comparison between single therapy and combination therapy. In the antidepressant and CBT comparison, effect sizes favoured CBT over antidepressants with a significant advantage for CBT on some outcome measures. Combined treatment appeared more effective than antidepressants. However, combined treatment did not emerge more effective than CBT.
Antidepressants may not be considered more efficacious than CBT for the acute treatment of depressed patients nor can combination therapy be regarded as more effective than CBT alone.
Worldwide, the Irish diaspora experience elevated psychiatric morbidity across generations, not accounted for through socioeconomic position. The present study assessed the contribution of intergenerational migration and settlementrelated adversity in accounting for adult mental health, in second generation Irish people.
Analysis of prospective data from a nationally representative birth cohort from Britain, comprising 17,000 babies born in a single week in 1958 and followed up to mid-life. Common mental disorders were assessed at age 44/ 45.
Relative to the rest of the cohort, second generation Irish children grew up in marked material and social disadvantage, which tracked into early adulthood. By mid-life, parity was reached between second generation Irish cohort members and the rest of the sample on most disadvantage indicators. At age 23 Irish cohort members were more likely to screen positive for common mental disorders (OR: 1.44; 95% CI: 1.06, 1.94). This had reduced slightly by mid-life (OR: 1.27; 95% CI: 0.96, 1.69). Adjustment for childhood and early adulthood adversity fully attenuated differences in adult mental health disadvantages.
Social and material disadvantage experienced in childhood continues to have long-range adverse effects on mental health at mid-life, in second generation Irish cohort members. This suggests important mechanisms over the lifecourse, which may have important policy implications in the settlement of migrant families.
Social capital is emerging as an important component of mental well-being. Our aim was to assess the relationship between social capital and common mental disorders and to explore the role of social capital in the relationship between deprivation and common mental disorders.
This study used data collected from 7023 adults in England who completed the Adult Psychiatric Morbidity Survey (2007). Common mental disorders (CMD) were measured using CIS-R. Questions on both cognitive (CSC) and structural social capital were included, as well as data on area level deprivation.
We found a strong association between higher CSC and lower levels of CMD, depression and anxiety. Structural social capital was associated with lower levels of CMD and depression but was not conclusively associated with lower levels of anxiety. While there is a relationship between low social capital and deprivation, we found that higher CSC was still associated with lower CMD in participants living in deprived areas. Results for structural social capital were less conclusive although an association with lower overall CMD was still found in the most deprived communities.
In a nationally representative sample, higher social capital is associated with lower levels of CMD. There appears to be a relationship between low social capital and deprivation and this may have implications for the mental wellbeing of individuals living in deprived communities.
Impaired insight is commonly seen in psychosis and some studies have proposed that is a biologically based deficit. Support for this view comes from the excess of neurological soft signs (NSS) observed in patients with psychoses and their neural correlates which demonstrate a degree of overlap with the regions of interest implicated in neuroimaging studies of insight. The aim was to examine the relationship between NSS and insight in a sample of 241 first-episode psychosis patients.
Total scores and subscale scores from three insight measures and two NSS scales were correlated in addition to factors representing overall insight and NSS which we created using principal component analysis.
There were only four significant associations when we controlled for symptoms. “Softer” Condensed Neurological Evaluation (CNE) signs were associated with our overall insight factor (r = 0.19, P = 0.02), with total Birchwood (r = −0.24, P<0.01), and the Birchwood subscales; recognition of mental illness (r = −0.24, P<0.01) and need for treatment (r = −0.18, P = 0.02). Total Neurological Evaluation Scale (NES) and recognition of the achieved effects of medication were also weakly correlated (r = 0.14, P = 0.04).
This study does not support a direct link between neurological dysfunction and insight in psychosis. Our understanding of insight as a concept remains in its infancy.
Cognitive impairment associated with lifetime major depressive disorder (MDD) is well-supported by meta-analytic studies, but population-based estimates remain scarce. Previous UK Biobank studies have only shown limited evidence of cognitive differences related to probable MDD. Using updated cognitive and clinical assessments in UK Biobank, this study investigated population-level differences in cognitive functioning associated with lifetime MDD.
Associations between lifetime MDD and cognition (performance on six tasks and general cognitive functioning [g-factor]) were investigated in UK Biobank (N-range 7,457–14,836, age 45–81 years, 52% female), adjusting for demographics, education, and lifestyle. Lifetime MDD classifications were based on the Composite International Diagnostic Interview. Within the lifetime MDD group, we additionally investigated relationships between cognition and (a) recurrence, (b) current symptoms, (c) severity of psychosocial impairment (while symptomatic), and (d) concurrent psychotropic medication use.
Lifetime MDD was robustly associated with a lower g-factor (β = −0.10, PFDR = 4.7 × 10−5), with impairments in attention, processing speed, and executive functioning (β ≥ 0.06). Clinical characteristics revealed differential profiles of cognitive impairment among case individuals; those who reported severe psychosocial impairment and use of psychotropic medication performed worse on cognitive tests. Severe psychosocial impairment and reasoning showed the strongest association (β = −0.18, PFDR = 7.5 × 10−5).
Findings describe small but robust associations between lifetime MDD and lower cognitive performance within a population-based sample. Overall effects were of modest effect size, suggesting limited clinical relevance. However, deficits within specific cognitive domains were more pronounced in relation to clinical characteristics, particularly severe psychosocial impairment.